Emil Olbrich, Head of LTE Research, Development, Testing and Evaluation, NIST is speaking in the Public Safety LTE track on Day Two of the LTE North America conference, taking place on the 21st-22nd November 2013, in Dallas, Texas, USA. Here we speak to him about what still needs to be worked on to get LTE up to speed for public safety requirements.

Are there still limitations with LTE technology that will need to be overcome in terms of providing mission-critical voice and data?

I would say that we need to prove out several of the key features within LTE that are intended to provide a better quality of experience to the end customer. These include the QoS and ARP features and how they’re implemented end-to-end, from the application to device, to RAN to EPC, to app server. The lack of a PTT implementation that meets all of public safety needs will also be something to be proven out or developed too. The use of VoLTE/RCS or an OTT application for telephony based voice/MMS/file transfer is also still being evaluated in order to determine what best meets the needs of public safety.

LTE is a fast evolving standard compared to previous public safety system. Will progressions such as LTE-Advanced have any bearing on the public safety standard?

LTE-Advanced will bring several important things for public safety. Speed is great but the increase in spectral efficiency will also increase the number of simultaneous users on the network and hopefully allow for better cell edge performance. Also the introduction of relay nodes will be important for extending coverage.

How will a Public Safety handset differ from a mainstream LTE handset?

The intent for LTE user equipment for public safety is to remain within the 3GPP LTE standards to reduce time to market, fragmentation and cost. Some users may require specific environmental features (e.g. intrinsically safe, works with gloves, larger speaker, discrete PTT button) and other 3GPP future releases will potentially include higher power and direct mode.

Why is the LTE North America conference such an important date in your diary?

The ability to meet the key vendors and carriers of LTE in a single place is by far the most appealing thing. Being able to interact with our peers in the LTE space and partake in the latest information regarding technology and analyst presentations is also key to keeping up with the latest innovations.